This is fairly straightforward, and can be done with a script attached to a rule that identifies the incoming messages by sender, but your question raises an important issue.
You indicate that you are wanting to download a particular attachment. Will that attachment always have the same name? If it does (or if it has the same name as a file already in the target folder) what do you want to do about the name clash. Do you wish to overwrite the existing file or preserve it?
The following when run from the aforesaid rule will extract all attachments to the named folder which must exist, Existing files are retained.
Code:
Public Sub SaveAttachments(olItem As MailItem)
'An Outlook macro by Graham Mayor
Dim olAttach As Attachment
Dim strFname As String
Dim strExt As String
Dim j As Long
'The folder to save the attachments
'This folder must exist
Const strSaveFldr As String = "C:\Path\Reports\"
On Error GoTo CleanUp
If olItem.Attachments.Count > 0 Then
For j = olItem.Attachments.Count To 1 Step -1
Set olAttach = olItem.Attachments(j)
If Not olAttach.FileName Like "image*.*" Then
strFname = olAttach.FileName
strExt = Right(strFname, Len(strFname) - InStrRev(strFname, Chr(46)))
strFname = FileNameUnique(strSaveFldr, strFname, strExt)
olAttach.SaveAsFile strSaveFldr & strFname
'olAttach.Delete 'delete the attachment
End If
Next j
olItem.Save
End If
CleanUp:
Set olAttach = Nothing
Set olItem = Nothing
lbl_Exit:
Exit Sub
End Sub
Private Function FileNameUnique(strPath As String, _
strFileName As String, _
strExtension As String) As String
'An Outlook macro by Graham Mayor
Dim lngF As Long
Dim lngName As Long
lngF = 1
lngName = Len(strFileName) - (Len(strExtension) + 1)
strFileName = Left(strFileName, lngName)
Do While FileExists(strPath & strFileName & Chr(46) & strExtension) = True
strFileName = Left(strFileName, lngName) & "(" & lngF & ")"
lngF = lngF + 1
Loop
FileNameUnique = strFileName & Chr(46) & strExtension
lbl_Exit:
Exit Function
End Function
Private Function FileExists(filespec) As Boolean
'An Outlook macro by Graham Mayor
Dim fso As Object
Set fso = CreateObject("Scripting.FileSystemObject")
If fso.FileExists(filespec) Then
FileExists = True
Else
FileExists = False
End If
lbl_Exit:
Exit Function
End Function